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</style></head><body><table border="0" cellpadding="0" cellspacing="0" width="100%"><tr /><td align="left" valign="top" width="32"><img align="left" border="0" height="32" src="images/rb-logo.png" width="32" /></td><td width="1">&#160;&#160;</td><td class="postheader" valign="center"><a href="index.html"><font color="#004faf">Home</font></a>&#160;&#183; <a href="classes.html"><font color="#004faf">All Classes</font></a>&#160;&#183; <a href="modules.html"><font color="#004faf">Modules</font></a></td></table><h1 align="center">QXmlName Class Reference<br /><sup><sup>[<a href="qtxmlpatterns.html">QtXmlPatterns</a> module]</sup></sup></h1><p>The QXmlName class represents the name of an XML node, in an
efficient, namespace-aware way. <a href="#details">More...</a></p>

<h3>Methods</h3><ul><li><div class="fn" /><b><a href="qxmlname.html#QXmlName">__init__</a></b> (<i>self</i>)</li><li><div class="fn" /><b><a href="qxmlname.html#QXmlName-2">__init__</a></b> (<i>self</i>, QXmlNamePool&#160;<i>namePool</i>, QString&#160;<i>localName</i>, QString&#160;<i>namespaceUri</i>&#160;=&#160;QString(), QString&#160;<i>prefix</i>&#160;=&#160;QString())</li><li><div class="fn" /><b><a href="qxmlname.html#QXmlName-3">__init__</a></b> (<i>self</i>, QXmlName)</li><li><div class="fn" />bool <b><a href="qxmlname.html#isNull">isNull</a></b> (<i>self</i>)</li><li><div class="fn" />QString <b><a href="qxmlname.html#localName">localName</a></b> (<i>self</i>, QXmlNamePool&#160;<i>query</i>)</li><li><div class="fn" />QString <b><a href="qxmlname.html#namespaceUri">namespaceUri</a></b> (<i>self</i>, QXmlNamePool&#160;<i>query</i>)</li><li><div class="fn" />QString <b><a href="qxmlname.html#prefix">prefix</a></b> (<i>self</i>, QXmlNamePool&#160;<i>query</i>)</li><li><div class="fn" />QString <b><a href="qxmlname.html#toClarkName">toClarkName</a></b> (<i>self</i>, QXmlNamePool&#160;<i>query</i>)</li></ul><h3>Static Methods</h3><ul><li><div class="fn" />QXmlName <b><a href="qxmlname.html#fromClarkName">fromClarkName</a></b> (QString&#160;<i>clarkName</i>, QXmlNamePool&#160;<i>namePool</i>)</li><li><div class="fn" />bool <b><a href="qxmlname.html#isNCName">isNCName</a></b> (QString&#160;<i>candidate</i>)</li></ul><h3>Special Methods</h3><ul><li><div class="fn" />bool <b><a href="qxmlname.html#__eq__">__eq__</a></b> (<i>self</i>, QXmlName&#160;<i>other</i>)</li><li><div class="fn" />int <b><a href="qxmlname.html#__hash__">__hash__</a></b> (<i>self</i>)</li><li><div class="fn" />bool <b><a href="qxmlname.html#__ne__">__ne__</a></b> (<i>self</i>, QXmlName&#160;<i>other</i>)</li></ul><a name="details" /><hr /><h2>Detailed Description</h2><p>The QXmlName class represents the name of an XML node, in an
efficient, namespace-aware way.</p>
<p>QXmlName represents the name of an XML node in a way that is
both efficient and safe for comparing names. Normally, an XML node
represents an XML element or attribute, but QXmlName can also
represent the names of other kinds of nodes, e.g., <a href="qabstractxmlreceiver.html#processingInstruction">QAbstractXmlReceiver.processingInstruction</a>()
and <a href="qabstractxmlreceiver.html#namespaceBinding">QAbstractXmlReceiver.namespaceBinding</a>().</p>
<p>The name of an XML node has three components: The <i>namespace
URI</i>, the <i>local name</i>, and the <i>prefix</i>. To see what
these refer to in XML, consider the following snippet.</p>
<pre class="cpp">
 &lt;book xmlns:dc='http://purl.org/dc/elements/1.1'
       xmlns='http://example.com/MyDefault'&gt;
     &lt;dc:title&gt;Mobey Dick&lt;/dc:title&gt; ...
 &lt;/book&gt;
</pre>
<p>For the element named <i>book</i>, <a href="qxmlname.html#localName">localName</a>() returns <i>book</i>,
<a href="qxmlname.html#namespaceUri">namespaceUri</a>() returns
<i>http://example.com/MyDefault</i>, and <a href="qxmlname.html#prefix">prefix</a>() returns an empty string. For
the element named <i>title</i>, <a href="qxmlname.html#localName">localName</a>() returns <i>title</i>,
<a href="qxmlname.html#namespaceUri">namespaceUri</a>() returns
<i>http://purl.org/dc/elements/1.1</i>, and <a href="qxmlname.html#prefix">prefix</a>() returns <i>dc</i>.</p>
<p>To ensure that operations with QXmlName are efficient, e.g.,
copying names and comparing them, each instance of QXmlName is
associated with a <a href="qxmlnamepool.html">name pool</a>, which
must be specified at QXmlName construction time. The three
components of the QXmlName, i.e., the namespace URI, the local
name, and the prefix, are stored in the name pool mapped to
identifiers so they can be shared. For this reason, the only way to
create a valid instance of QXmlName is to use the class
constructor, where the <a href="qxmlnamepool.html">name pool</a>,
local name, namespace URI, and prefix must all be specified.</p>
<p>Note that QXmlName's default constructor constructs a null
instance. It is typically used for allocating unused entries in
collections of QXmlName.</p>
<p>A side effect of associating each instance of QXmlName with a
<a href="qxmlnamepool.html">name pool</a> is that each instance of
QXmlName is tied to the <a href="qxmlnamepool.html">QXmlNamePool</a> with which it was created.
However, the QXmlName class does not keep track of the name pool,
so all the accessor functions, e.g., <a href="qxmlname.html#namespaceUri">namespaceUri</a>(), <a href="qxmlname.html#prefix">prefix</a>(), <a href="qxmlname.html#localName">localName</a>(), and <a href="qxmlname.html#toClarkName">toClarkName</a>() require that the
correct name pool be passed to them. Failure to provide the correct
name pool to these accessor functions results in undefined
behavior.</p>
<p>Note that a <a href="qxmlnamepool.html">name pool</a> is
<i>not</i> an XML namespace. One <a href="qxmlnamepool.html">name
pool</a> can represent instances of QXmlName from different XML
namespaces, and the instances of QXmlName from one XML namespace
can be distributed over multiple <a href="qxmlnamepool.html">name
pools</a>.</p>
<a id="comparing-qxmlnames" name="comparing-qxmlnames" /><a id="comparing-qxmlnames" name="comparing-qxmlnames" />
<h3>Comparing QXmlNames</h3>
<p>To determine what a QXmlName refers to, the <i>namespace URI</i>
and the <i>local name</i> are used. The <i>prefix</i> is not used
because the prefix is simply a shorthand name for use in place of
the normally much longer namespace URI. Nor is the prefix used in
name comparisons. For example, the following two element nodes
represent the same element and compare equal.</p>
<pre class="cpp">
 &lt;svg xmlns="http://www.w3.org/2000/svg"/&gt;
</pre>
<pre class="cpp">
 &lt;x:svg xmlns:x="http://www.w3.org/2000/svg"/&gt;
</pre>
<p>Although the second name has the prefix <i>x</i>, the two names
compare equal as instances of QXmlName, because the prefix is not
used in the comparison.</p>
<p>A local name can never be an empty string, although the prefix
and namespace URI can. If the prefix is not empty, the namespace
URI cannot be empty. Local names and prefixes must be valid
<a href="http://www.w3.org/TR/REC-xml-names/#NT-NCName">NCNames</a>,
e.g., <i>abc.def</i> or <i>abc123</i>.</p>
<p>QXmlName represents what is sometimes called an <i>expanded
QName</i>, or simply a QName.</p>
<hr /><h2>Method Documentation</h2><h3 class="fn"><a name="QXmlName" />QXmlName.__init__ (<i>self</i>)</h3><p>Constructs an uninitialized <a href="qxmlname.html">QXmlName</a>. To build a valid <a href="qxmlname.html">QXmlName</a>, you normally use the other
constructor, which takes a <a href="qxmlnamepool.html">name
pool</a>, namespace URI, local name, and prefix as parameters. But
you can also use this constructor to build a null <a href="qxmlname.html">QXmlName</a> and then assign an existing <a href="qxmlname.html">QXmlName</a> to it.</p>
<p><b>See also</b> <a href="qxmlname.html#isNull">isNull</a>().</p>


<h3 class="fn"><a name="QXmlName-2" />QXmlName.__init__ (<i>self</i>, <a href="qxmlnamepool.html">QXmlNamePool</a>&#160;<i>namePool</i>, QString&#160;<i>localName</i>, QString&#160;<i>namespaceUri</i>&#160;=&#160;QString(), QString&#160;<i>prefix</i>&#160;=&#160;QString())</h3><p>Constructs a <a href="qxmlname.html">QXmlName</a> instance that
inserts <i>localName</i>, <i>namespaceURI</i> and <i>prefix</i>
into <i>namePool</i> if they aren't already there. The accessor
functions <a href="qxmlname.html#namespaceUri">namespaceUri</a>(),
<a href="qxmlname.html#prefix">prefix</a>(), <a href="qxmlname.html#localName">localName</a>(), and <a href="qxmlname.html#toClarkName">toClarkName</a>() must be passed the
<i>namePool</i> used here, so the <i>namePool</i> must remain in
scope while the accessor functions might be used. However, two
instances can be compared with <i>==</i> or <i>!=</i> and copied
without the <i>namePool</i>.</p>
<p>The user guarantees that the string components are valid for a
QName. In particular, the local name, and the prefix (if present),
must be valid <a href="http://www.w3.org/TR/REC-xml-names/#NT-NCName">NCNames</a>. The
function <a href="qxmlname.html#isNCName">isNCName</a>() can be
used to test validity of these names. The namespace URI should be
an absolute URI. <a href="qurl.html#isRelative">QUrl.isRelative</a>() can be used to test
whether the namespace URI is relative or absolute. Finally,
providing a prefix is not valid when no namespace URI is
provided.</p>
<p><i>namePool</i> is not copied. Nor is the reference to it
retained in this instance. This constructor inserts the three
strings into <i>namePool</i>.</p>


<h3 class="fn"><a name="QXmlName-3" />QXmlName.__init__ (<i>self</i>, <a href="qxmlname.html">QXmlName</a>)</h3><h3 class="fn"><a name="fromClarkName" /><a href="qxmlname.html">QXmlName</a> QXmlName.fromClarkName (QString&#160;<i>clarkName</i>, <a href="qxmlnamepool.html">QXmlNamePool</a>&#160;<i>namePool</i>)</h3><p>Converts <i>clarkName</i> into a <a href="qxmlname.html">QXmlName</a>, inserts into <i>namePool</i>, and
returns it.</p>
<p>A clark name is a way to present a full QName with only one
string, where the namespace cannot contain braces. Here are a
couple of examples:</p>
<table class="generic">
<thead>
<tr class="qt-style">
<th>Clark Name</th>
<th>Description</th>
</tr>
</thead>
<tr class="odd" valign="top">
<td><tt>html</tt></td>
<td>The local name <tt>html</tt>, in no namespace</td>
</tr>
<tr class="even" valign="top">
<td><tt>http://www.w3.org/1999/xhtml</tt>html</td>
<td>The local name <tt>html</tt>, in the XHTML namespace</td>
</tr>
<tr class="odd" valign="top">
<td><tt>http://www.w3.org/1999/xhtml</tt>my:html</td>
<td>The local name <tt>html</tt>, in the XHTML namespace, with the
prefix <tt>my</tt></td>
</tr>
</table>
<p>If the namespace contains braces, the returned value is either
invalid or has undefined content.</p>
<p>If <i>clarkName</i> is an invalid name, a default constructed
<a href="qxmlname.html">QXmlName</a> is returned.</p>
<p>This function was introduced in Qt 4.5.</p>
<p><b>See also</b> <a href="qxmlname.html#toClarkName">toClarkName</a>().</p>


<h3 class="fn"><a name="isNCName" />bool QXmlName.isNCName (QString&#160;<i>candidate</i>)</h3><p>Returns true if <i>candidate</i> is an <tt>NCName</tt>. An
<tt>NCName</tt> is a string that can be used as a name in XML and
<a href="xmlprocessing.html">XQuery</a>, e.g., the prefix or local
name in an element or attribute, or the name of a variable.</p>
<p><b>See also</b> <a href="http://www.w3.org/TR/REC-xml-names/#NT-NCName">Namespaces in XML
1.0 (Second Edition), [4] NCName</a>.</p>


<h3 class="fn"><a name="isNull" />bool QXmlName.isNull (<i>self</i>)</h3><p>Returns true if this <a href="qxmlname.html">QXmlName</a> is not
initialized with a valid combination of <i>namespace URI</i>,
<i>local name</i>, and <i>prefix</i>.</p>
<p>A valid local name is always required. The prefix and namespace
URI can be empty, but if the prefix is not empty, the namespace URI
must not be empty. Local names and prefixes must be valid <a href="http://www.w3.org/TR/REC-xml-names/#NT-NCName">NCNames</a>, e.g.,
<i>abc.def</i> or <i>abc123</i>.</p>


<h3 class="fn"><a name="localName" />QString QXmlName.localName (<i>self</i>, <a href="qxmlnamepool.html">QXmlNamePool</a>&#160;<i>query</i>)</h3><p>Returns the local name.</p>
<p>Note that for efficiency, the local name string is not stored in
the <a href="qxmlname.html">QXmlName</a> but in the <a href="qxmlnamepool.html">QXmlNamePool</a> that was passed to the
constructor. Hence, that same <i>namePool</i> must be passed to
this function, so it can be used for looking up the local name.</p>


<h3 class="fn"><a name="namespaceUri" />QString QXmlName.namespaceUri (<i>self</i>, <a href="qxmlnamepool.html">QXmlNamePool</a>&#160;<i>query</i>)</h3><p>Returns the namespace URI.</p>
<p>Note that for efficiency, the namespace URI string is not stored
in the <a href="qxmlname.html">QXmlName</a> but in the <a href="qxmlnamepool.html">QXmlNamePool</a> that was passed to the
constructor. Hence, that same <i>namePool</i> must be passed to
this function, so it can be used for looking up the namespace
URI.</p>


<h3 class="fn"><a name="prefix" />QString QXmlName.prefix (<i>self</i>, <a href="qxmlnamepool.html">QXmlNamePool</a>&#160;<i>query</i>)</h3><p>Returns the prefix.</p>
<p>Note that for efficiency, the prefix string is not stored in the
<a href="qxmlname.html">QXmlName</a> but in the <a href="qxmlnamepool.html">QXmlNamePool</a> that was passed to the
constructor. Hence, that same <i>namePool</i> must be passed to
this function, so it can be used for looking up the prefix.</p>


<h3 class="fn"><a name="toClarkName" />QString QXmlName.toClarkName (<i>self</i>, <a href="qxmlnamepool.html">QXmlNamePool</a>&#160;<i>query</i>)</h3><p>Returns this <a href="qxmlname.html">QXmlName</a> formatted as a
Clark Name. For example, if the local name is <tt>html</tt>, the
prefix is <tt>x</tt>, and the namespace URI is
<tt>http://www.w3.org/1999/xhtml/</tt>, then the Clark Name
returned is:</p>
<pre class="cpp">
 {http:<span class="comment">//www.w3.org/1999/xhtml/}x:html.</span>
</pre>
<p>If the local name is <i>MyWidget</i> and the namespace is empty,
the Clark Name returned is:</p>
<pre class="cpp">
 MyWidget
</pre>
<p>Note that for efficiency, the namespace URI, local name, and
prefix strings are not stored in the <a href="qxmlname.html">QXmlName</a> but in the <a href="qxmlnamepool.html">QXmlNamePool</a> that was passed to the
constructor. Hence, that same <i>namePool</i> must be passed to
this function, so it can be used for looking up the three string
components.</p>
<p>This function can be useful for debugging.</p>
<p><b>See also</b> <a href="http://www.jclark.com/xml/xmlns.htm">XML Namespaces, James
Clark</a> and <a href="qxmlname.html#fromClarkName">fromClarkName</a>().</p>


<h3 class="fn"><a name="__eq__" />bool QXmlName.__eq__ (<i>self</i>, <a href="qxmlname.html">QXmlName</a>&#160;<i>other</i>)</h3><h3 class="fn"><a name="__hash__" />int QXmlName.__hash__ (<i>self</i>)</h3><h3 class="fn"><a name="__ne__" />bool QXmlName.__ne__ (<i>self</i>, <a href="qxmlname.html">QXmlName</a>&#160;<i>other</i>)</h3><address><hr /><div align="center"><table border="0" cellspacing="0" width="100%"><tr class="address"><td align="left" width="25%">PyQt&#160;snapshot-4.9.5-9eb6aac99275 for X11</td><td align="center" width="50%">Copyright &#169; <a href="http://www.riverbankcomputing.com">Riverbank&#160;Computing&#160;Ltd</a> and <a href="http://www.qtsoftware.com">Nokia</a> 2012</td><td align="right" width="25%">Qt&#160;4.8.3</td></tr></table></div></address></body></html>